The present invention relates to a crystal growth device and an installation having means for observing the crystallization.
One of the methods of studying macromolecular substances consists in forming crystals of said substances and subjecting said crystals to examination, particularly spectrography. To form such crystals, diffusion methods are used, possibly through a porous diffusion wall. For this, a crucible filled with a liquid mixture of the macromolecular substance to be studied and a precipitating agent in a concentration insufficient for acting, is placed in an enclosure, then such a precipitating agent is introduced into said enclosure for causing crystallization by reducing the concentration of substance (liquid phase) or increasing it (vapor phase) or with constant concentration (dialysis).
By diffusion, the concentration of the mixture of precipitating agent and macromolecular substance contained in the crucible tends to align itself on that of the precipitating agent contained in the enclosure. Consequently, by varying the concentration of the precipitating agent, the crystallization of said macromolecular substance can be adjusted.
Generally, the crucible and the enclosure are at least partially transparent, so that an operator may visually follow the development of crystallization. However, such visual observation cannot be precise. In addition, it becomes difficult, if not impossible, if said crucible is of a small size and/or if a plurality of experiments are conducted simultaneously using an installation combining a plurality of crucibles, close together.
Furthermore, the crystals obtained in land-based laboratories using such diffusion techniques are not perfect, not only from the quality but also from the size point of view, particularly because of convection phenomena due to gravity.
To overcome this drawback, it is advantageous to be able to use such diffusion techniques on board space vessels, for then the conditions of weightlessness eliminate such convection phenomena.
It goes without saying that such use in space of crystal growth methods involves the miniaturization of the crucibles and of the installations grouping them together. It is then necessary to provide an automatic system for observing the crystal growth reactions.